Midnight Mischief
by tristinai
Summary: Model student Elsa gets caught up in Jack's antics and the two soon find themselves hiding in a broom closet. (JELSA, Hogwarts AU, Oneshot, Smut)


**Rating:** M  
**Word Count:** 4000  
**Genre: **Hogwarts AU  
**Warnings:** Descriptive sex  
**A/N:** Excuse the formatting, I am being driven crazy by . This was originally posted on Tumblr but I have decided to add it on here so any feedback you can provide will be greatly appreciated :).

**Summary: **Model student Elsa gets caught up in Jack's antics and the two soon find themselves hiding in a broom closet.

Elsa's footsteps echoed loudly in in the halls, the night so eerily quiet that she could hear the swishing of her robes. With final exams in full session, a solemn calm had fallen over the student body all week, many students abandoning their late night antics for last minute cramming. But even with the pressure of N.E.W.T.s and O.W.L.s to discourage rule breaking, the duties of Head Boy and Girl became more stringent as they were expected to keep the calm and provide the best possible studying atmosphere for the next few weeks.

Elsa may take great pride in being selected Head Girl. Still, it didn't change how much she disliked having to patrol the halls just after curfew to make sure nobody was sneaking out of their dorms.

She turned at the corner, heading down a hallway lined with portraits on both sides. Most of the occupants rested, one wizard even snoozing, disrupting the quiet that had followed her most of the way as she was finishing off her rounds. Part of her was impatient to get back to Ravenclaw tower so she could fit in another hour or so of reviewing Arithmancy. Another part of her, one she would be hard-pressed to own up to, was more than a little nervous wandering alone in this part of the castle.

_You've done this before, _she tried reasoning. _There's nothing to be afraid of._

Maybe if she was her 10 year old self tucked away in the Muggle world, she would try telling herself there's no such thing as ghosts. But 7 years at Hogwarts had more than proven this was not the case.

A sudden _swish_ gave her pause. She swore she had seen a shadow ducking into the corridor she had just walked by. A cold chill tickled down her spine. She slowly turned to peer down the dark, unlit hallway but she couldn't make out anything in the shadows.

"H-hello?" she called out in a shaky voice.

Suddenly, a dark form screeched and fell from the wall towards her. Elsa cried out in surprise, ducking down and dropping her wand. The bat fluttered around her for a moment before flying off in search of the evening sky.

Elsa breathed in deeply, her heart thudding heavily in her chest. After a good minute, she released a small laugh, bending down to retrieve her wand.

_At least Hiccup wasn't with me this time, _she thought, with a smile. _He'd never let this go!_

To try and cover more in less time, her and Hiccup, the Head Boy, had agreed to monitor different sections of the castle. Once she was finished down here, she was expected to meet up with him and give her report.

She was about to continue her trek down the main hallway when the torches on either side of her suddenly went out. The chill had returned but she tried telling herself it was just the wind.

_Because it gets sooo windy in June,_ kicked in her paranoia.

That was when she heard it. Like a breathless whisper, seeming to call to her from the unlit corridor. She was so terrified that she didn't dare move. She wanted to ignore it and return to her dorm but she was the Head Girl. It was her job to investigate and make sure this wasn't a student playing a prank on her.

_Whoever it is, I'll drag them to Headmaster Moon and let him deal with it, _she decided, swallowing uncomfortably. _If it's a student…_

She whispered _Lumos_ and the tip of her wand lit up. She tried stretching her arm as far as it would go but the dull light that was cast hardly gave her visibility. She would have to enter the corridor.

She took a small step forward. Then another. So far, she couldn't see anything out of the ordinary. As she stepped with forced confidence, she berated herself for being so scared.

_I must be hearing things, _she thought.

And she believed that. Until she was just over halfway down the corridor.

_Patter. Patter. Patter._

The sound of nimble footsteps coming behind her made her blood run cold.

She quickly turned, wand held out in front of her. "W-who's there?"

But she was only met with silence.

_I'm losing it, _she thought, trying to calm her racing heart with another deep breath.

_Scraaaape._

Like nails over stone, the onerous sound came from deeper down the corridor. Elsa's hands were shaking so visibly, she was half surprised she hadn't dropped her wand again. She wanted to leave, her _flight _response screaming at her body to move. But up ahead, at the edge of where the wand's light reached, she could just barely make out a figure.

_Good,_ she nearly sighed, feeling her confidence return. _It's just a student._

A student who was about to get a piece of her mind.

She hesitantly stepped towards the figure, her footsteps once again echoing off the walls. It was the only sound that filled the space as she closed the distance between her and the shadow.

"You know the rules," she said, stepping in front of the figure, "no leaving the dorm past cur—"

Her voice trailed off, brows furrowing in confusion as she stared into a stone face. "A statue?"

_But then what was the sound I heard?_

"_Elsaaa….." _came a soft, snakelike whisper.

Elsa whipped around, waving the wand in front of her. But she couldn't see anything. A sick sense of dread curled inside of her, gripping her with ice-cold fear. She had to get out of here.

She turned on her heel and—

"Boo!"

Elsa gave a blood curling scream that ripped off the walls. She swore her heart had literally stopped as she clutched desperately at her wand.

But once the echoes of her screams subsided, the corridor was filled with the laughter of none other than one Jack Frost.

Holding his sides, he was nearly bent over. His laughter, which came at the expense of Elsa losing her usually carefully controlled composure, had Elsa's cheeks flush with anger.

"JACK FROST! I AM GOING TO USE EVERY UNFORGIVABLE CURSE AND A RESURRECTION STONE ON YOU SO I CAN DO IT ALL OVER AGAIN!"

Jack managed to pick himself up, leaning against the wall as he struggled to regain his breath. "You—you should have seen—your face!"

Boyfriend or not, she was quickly forgetting why the unforgiveables were unforgiveable.

But instead of committing the magic equivalent of homicide, she turned on her heel and began storming down the hall. "Congratulations, Mr. Frost, you have just earned yourself a meeting with the Headmaster."

That seemed to finally silence his laughter. She could hear him quickly reach pace behind her. "Elsa? C'mon, you wouldn't really report your _own _boyfriend? It was just a joke!"

She spun quickly and poked him angrily in the chest. "Jack, you know the rules. I can't show favoritism by covering up for you. I'm the Head Girl. And right now, I'm not in the mood for your games!"

But as she saw his expression fell, she almost felt bad for coming off so hard on him. _Almost._

"I was just having fun," he said, quietly.

She could see how apologetic he looked, even if he hadn't quite said _Sorry_ yet.

"It's passed curfew," Elsa said, with an irritated sigh. "You should be in the dungeons right now studying for the N.E.W.T.s."

"Yeah, I know," he said, reaching out to gently grasp her wrist, "but I missed you, Elsa."

She wanted to be stubborn because risking detention just to sneak out and meet her was not the kind of behavior she should be condoning as Head Girl. But with his thumb tracing slow circles over her wrist, she could already feel her pulse start to pick up again.

"You saw me last night. We studied together," she tried to argue.

Jack rolled his eyes. "_You _studied. I kept falling asleep and you kicked me out of the library. That doesn't count."

"You were distracting me," she complained, though she had felt a little guilty when Jack left looking like a kicked boarhound, "Potions is my most difficult subject and I can't concentrate with your snoring."

"All you've been doing is studying lately."

"It's the N.E.W.T.s, Jack," Elsa said, wondering why she even needed to remind him, "I need to pass them to graduate."

"Yeah but all you do is study and your Head Girl duties," Jack complained, "I feel like I never see you anymore."

She wanted to say he was wrong, that they saw each other almost every day. But unless Jack was quietly focused on a book (which he never was), she either ended their study session early to find some place quieter to study alone, or she canceled any attempts to get together to review material she was struggling with. She actually had been neglecting him, even if it wasn't intentional.

"You're right," she said, looking up at him apologetically. "I've let the stress of the N.E.W.T.s get to me. I wasn't trying to ignore you."

She leaned up and kissed his lips softly, wrapping her arms his neck. "Forgive me?"

His arms snaked into her robe, encircling her waist and pulling her closer to him. He teasingly bumped his nose against hers, murmuring "of course", before tilting his head down for another kiss. It began as a gentle brushing of lips, like a whisper against her skin. But there was a heat that had been building from her weeks of voluntary isolation and she soon wondered why she had ever willingly denied herself this. Kissing Jack Frost was like taking a shot of Firewhiskey, burning her in a way that only made her want more.

His tongue teased her bottom lip, seeking desired entrance. She moaned softly as it was gained, fingers grasping at wild locks of silver hair. Pressed this close to him, she could feel how much he wanted her and it sent fire burning through her veins. Merlin, how badly she needed this right now!

"Elsa," he groaned, his lips leaving hers to trail along her neck. She tilted her head to the side, his name leaving her parted lips as he began to suckle gently at the neglected flesh.

But any thoughts of taking it a step further were effectively ceased as the sound of loud footsteps echoed off the walls of the main hall.

"It's after curfew," she said, her face going pale, "if they find us still out here—"

Jack groaned and dropped his head on her shoulder, his erection digging into her side. "There goes my fun…"

"Jack, this is serious!" Elsa whispered frantically, disentangling herself. She ignored his pout. "I've never had detention before!"

The footsteps were getting louder, just beyond the corner of the corridor. The only source of light was the one she held in her hand. She quietly cast _Nox_, the light at the tip of her wand fading until they were completely surrounded in darkness. She felt Jack at her side, tugging her and pulling her with him against the wall.

"We'll sneak you back in," Jack promised. "We'll have to give Mr. Equus the slip."

Maximus Equus was the most feared and hated caretaker of Hogwarts. He was known to relentlessly pursue any students found outside of their dorms and took great joy in their punishment. Elsa had never managed to get on his bad side but she knew that Jack, and his dorm mate Flynn, were at the top of Mr. Equus' List.

The torches that burned out earlier were relit and Elsa could just make out a figure in the shadows that the light cast.

"He's going to find us," Elsa said worriedly. She shrank back closer to Jack, willing herself to blend in with the shadows. But it was all futile. As soon as he turned down the hallway…

"Elsa…do you feel that?"

She felt Jack's hand move around blindly in the dark, tracing the wall behind them. Her curiosity getting the best of her, she did the same and felt cold metal beneath her hand.

"A door!"

But she swore she hadn't seen one there before…

"Come on."

The door creaked open and Elsa cringed. That definitely was going to get the caretaker's attention! But there was no way she was going to risk having this on her record so she let Jack pull her in with him. He quietly shut the door behind them, and they both waited with bated breath. After a few minutes, Jack sighed in relief.

"I think we're in the clear," he said.

Elsa was pressed against him, her hands clutching his robes. She couldn't even make out his face. It was darker in here than it had been in the corridor.

"Where are we?" she whispered. She attempted to take a step back from him but found she could barely move.

Jack casted _Lumos_, revealing a tiny storage space so packed with paraphernalia that neither of them could move without knocking something over.

"A broom closet?"

"And a book closet, a cauldron closet, a—hey, is that a dead rat?"

Elsa gave a small shriek and buried her face in Jack's chest, earning a small chuckle from him. "I just want to get back to my books and my dorm," she mumbled into his chest.

Jack soothingly rubbed her back, planting a small kiss on her head. The rational part of her brain chided her for being so scared, the effects of Jack's prank not quite having worn off, but she had to admit, it was nice to have these stolen moments with him. "We'll leave in a few minutes," Jack said, squeezing her gently, "Epuus may still be wandering around."

"What are we supposed to do until then?"

"Oh," Jack said, with a mischievous smirk, "I can think of a few things."

He placed his wand on the book shelf behind Elsa, pushing her back against it as he pressed himself into her. Elsa looked at him wide-eyed, every protest sitting on the tip of her tongue because….so help her, she was not going to be caught doing _that _in a broom closet. But any objection she had died as he brought their lips together, his hand cupping her chin. The intense heat from earlier returned as his tongue stroked against hers, a hand running down over her curves.

From there, things escalated quickly. His fingers loosened the navy and bronze tie on her neck before moving to deftly unhook the buttons of her blouse. Elsa shivered as the cool air in the storage room hit her exposed skin, a trail of goose bumps forming down to the valley between her breasts. But where the air licked her skin with its unforgiving chill, Jack's mouth brought desired heat as he kissed a wet, sloppy trail down from her neck.

Pushing the fabric aside, he licked a small stripe over her cleavage, causing Elsa to shiver. His thumb brushed over a nipple that had hardened beneath the thin, lacy material of her bra. With a quick flick of his fingers, her breasts were released from their constraints and she thanked Lady Luck for choosing to wear a bra with a front clasp that day.

"Jack," she moaned, her nails digging into his shoulder as his lips rolled over the hardened bud. She released a breathy gasp as he suckled on it, arching into his touch. She knew she was dripping a storm in her underwear but the fingers that lightly caressed her thigh promised respite from her growing arousal.

His hand tucked beneath her skirt moved to stroke the heat coming from between her legs. She whimpered as his fingers traveled over her panties, gaining entrance and slipping inside. With his fingers sliding between her folds, she had to bite her lip to keep from crying out. Even if she was mostly confident in their remaining undiscovered, she was embarrassed by how easily she came undone at Jack's hands.

"You're so wet," he murmured, pushing a finger inside of her. It was his turn to groan at the resistance he was met with. He thumbed her clitoris, pressing up just enough to have her keening against him. As he slipped another finger into her, his head fell to her shoulder and he whispered, "Merlin, I want to be inside of you."

Her hand pressed against the front of his trousers and she could feel just how badly he wanted it. The fingers pushing into her had her mind whirling, her thighs quivering around Jack's hand. But still, it wasn't enough. She wanted to be filled completely by him, feel him spill inside of her.

She undid his trousers, the ease at which it came making her wonder what it must say about their sex life. Her hand slipped into his boxers, gripping his erection firmly as Jack shuddered against her. With a confident pump along the length, her thumb circling slowly over the tip, she soon had Jack coming apart and thrusting into her hand.

"Elsa," he moaned, his fingers pumping into her with more need.

She jerked him a few more times, a faint blush coloring her cheeks. "Jack…"

He looked into her eyes and it was all the permission he needed. He pulled his fingers out of Elsa, tugging her underwear down so she could step out of them. They were still both clothed in their robes and school uniforms but desperation overcame practicality as Jack yanked his trousers and boxers down to his knees and shifted their position.

Lifting her left leg so she could wrap it around his waist, Jack pressed against her entrance, resting his forehead against hers with a shaky breath. Elsa's thighs trembled in anticipation but what little rational thought she was capable of kept her from grinding down on his cock.

"The charm," she whispered. She dug into her robes and pulled out her wand, casting a quick protection charm to prevent any unwanted consequences.

With her wand safely tucked away, Jack kissed her softly and she was almost surprised about the amount of control he had. Then again, he was always extremely patient when it came to her consent, even if he was hard and poking into her folds.

"Now?"

She nodded shyly.

As he pushed into her, Elsa's hands gripped his robes, the sensation of being filled causing a pleasing trill to slink up her spine. Steadying himself, Jack shuddered as he adjusted to the tight heat, her warmth blanketing his cock like a firm grip, before pulling out slowly and pushing in again more confidently. Elsa's leg squeezed his waist, drawing him in as far as he could go and from there, they began to build a steady rhythm, guided by each other's moans.

Hands weaving into hair, lips tasting every inch of exposed skin, it wasn't long before they became a mess of tangled limbs, their breathy gasps echoing off the walls of the storage closet. Each thrust warmed Elsa to her core, her head spinning from the dizzying pleasure of Jack's sounds, Jack's body, Jack's lips...she was completely numb to even her back hitting the bookshelf as their hips rocked together. With sweat dripping from Jack's forehead, falling onto her exposed cleavage, the hot, uncontrolled dance that they had begun only had Elsa's body craving more, her thighs bewitching Jack until he was slamming into her and groaning with careless abandon.

"Elsa," Jack moaned loudly, "Merlin, I don't know how long I can—"

She could feel it building, his desperation as he struggled to hold back to try and bring her with him. But he was tumbling too fast into his euphoria and she was right there with him, guiding him to a much needed release. Her fingers lacing into his mussed, silver locks, his name left her lips like a desperate plea and it was all it took for him to let go. His body stiffened, a hand firmly gripping the bookshelf, and suddenly he was crying out her name and spilling liquid hot inside of her. Her leg drew him closer, her other only barely holding them up, as he emptied himself with a final gasp. Unable to stand firmly on his shaking legs, he dropped into her embrace, breathing hard.

For minutes, both of them remained silent, stealing each other's warmth even as they continued to sweat in their heavy robes. Once Elsa regained her breath, she kissed Jack softly and he rested his dripping forehead against hers.

"I need a shower," he chuckled.

Now that they were starting to come down from their high, Elsa grimaced a little as she realized how sweat-soaked her robes were.

"You're not the only one," she added.

Jack slowly pulled himself out of her, the sensation of being separated making Elsa feel a little cold. She drew her arms tightly around him, keeping him close, sweat be damned. He smiled and kept his arms wrapped around her waist.

"First time in a closet," Jack pointed out, with a bit of a smirk, "how would you rank it?"

Elsa quirked a brow. "You want me to be honest?"

"…now I'm getting worried," he replied, with a nervous laugh.

"I'd give it a 7."

Jack's expression fell. "You didn't finish?"

But it came out as more of a statement than a question. Elsa looked away a bit bashful, also feeling a bit guilty, since she really shouldn't rank their intimacy based on how many orgasms she has. Then again, he did ask for honesty.

She gasped in surprise as she felt fingers slip into her dripping sex, looking back at Jack. The glint in his eyes and confident smile made a blush spread across her cheeks.

"Well, let's go for a 10, shall we?"

He kissed her a final time and, with a cheeky wink, dropped down to his knees. She barely had time to breathe before she felt his tongue slide into her so intimately, the only sound she could make was Jack's name until she came.

* * *

It must have been past midnight by the time the couple emerged out of the corridor, clothing askew and hair completely disheveled. Elsa was still dizzy from having come so hard, she was surprised she could even walk straight. She stumbled into Jack, who wrapped a protective arm around her and grinned down at her.

"Now would you give it a 10?"

Elsa giggled. "Well…maybe a 9 and a half…"

"You are one tough witch to please," Jack complained, though his lips tugged into a small smile. He pulled her in closer, dipping his head to kiss her chastely.

"Miss Lindstrom, Mr. Frost."

Jack and Elsa immediately pulled apart, both of them going extremely red. Standing before them, looking more bored than annoyed, was the Defense Against the Dark Arts Instructor and head of Slytherin, Professor Black. He took in their appearance, his golden eyes passing over Elsa and then Jack, and raised a quizzical brow. Elsa felt her heart plummet to her stomach.

"It is well past curfew," Professor Black continued. "Do you have any reason to be outside of your dorms?"

Elsa's face was beet red and she seemed to lose her ability to speak. The excuses she should have been making were not coming as her mind drew a blank.

"I believe a visit to the Headmaster is in order."

As Jack and Elsa silently followed Professor Black to the headmaster's office, Elsa could see her perfect record at Hogwarts crumble before her eyes. Beside her, Jack couldn't stop smirking and his indifference to her apprehension was getting a little on her nerves.

"What's so funny?" she demanded, keeping her voice low.

"You gotta admit," Jack said, "even if we get detention, it was so worth it."

Elsa mentally noted to hex Jack later.


End file.
